1. Field of the Invention
One disclosed aspect of the embodiments relates to a detecting apparatus applied to, for example, a medical diagnostic imaging apparatus, a nondestructive inspection apparatus, or an analysis apparatus using radiation, and a detecting system.
2. Description of the Related Art
Thin film semiconductor producing techniques have been used to make detecting apparatuses that include an array (pixel array) of pixels each including a combination of a switching element, such as a thin film transistor (TFT), and a converting element, such as a photodiode, for converting radiation or light into charge. Japanese Patent Laid-Open No. 2002-026300 discloses a related-art detecting apparatus which includes a switching element disposed on a substrate, a converting element disposed over the switching element and electrically connected thereto, and an interlayer insulating layer disposed between the converting element and each of the substrate and the switching element. This converting element includes a pixel electrode electrically connected to the switching element, a counter electrode disposed opposite the pixel electrode, a semiconductor layer disposed between the pixel electrode and the counter electrode, and an impurity semiconductor layer disposed between the pixel electrode and the semiconductor layer. The pixel electrode includes transparent conductive oxide in order to achieve efficient light irradiation for after-image reduction. Japanese Patent Laid-Open No. 2007-329434 discloses a related-art radiation imaging apparatus which includes a pixel electrode having a gap in a region where a semiconductor layer is disposed in order to achieve efficient light irradiation for after-image reduction.
A disadvantage of the structure disclosed in Japanese Patent Laid-Open No. 2002-026300 is incompatibility between adhesion of the impurity semiconductor layer to the transparent conductive oxide and dark current characteristics of the converting element. As the adhesion between the impurity semiconductor layer and the transparent conductive oxide is improved, the dark current characteristics of the converting element are degraded. On the other hand, as the dark current characteristics of the converting element are improved, the adhesion between the impurity semiconductor layer and the transparent conductive oxide is degraded. As regards the structure disclosed in Japanese Patent Laid-Open No. 2007-329434, the gap in the pixel electrode increases connection resistance between the converting element and the switching element. Unfortunately, it may be difficult to ensure a transfer rate enough to yield a frame rate of, for example, 30 fps.